In a vehicle air conditioner that is mounted on an electric vehicle, a hybrid vehicle, or the like, an electric compressor with an inverter integrally installed in the compressor is used. In such electric compressors, a three phase AC motor to which three-phase alternating current power converted via an inverter is applied is used as the motor for driving the compressor. Such an inverter-integrated electric compressor is required to be miniaturized as much as possible for being mounted in the inside of an engine room, and accordingly the motor is also eagerly required to be miniaturized.
As the above described three-phase AC motor, a concentrated wound (also called series wound) motor is used, and in the stator thereof, the connecting wires of stator winding wires of respective phases U, V and W that are wound on the tooth portions of a stator iron core via insulating bobbins and the neutral point at which the distal ends of the winding wires are star-connected are typically arranged outside the bobbins. Therefore, the outer shape of the stator itself tends to be large, which is not sufficiently compatible with the need for miniaturization of the motor.
Meanwhile, PTL 1 discloses an electric motor constituted of a main wire-wound body in which a main winding wire is continuously wound in series on a plurality of split iron cores via connecting wires by concentrated winding, and an auxiliary wire-wound body in which an auxiliary winding wire is continuously wound in series on a plurality of split iron cores via connecting wires by concentrated wiring. In the electric motor, extended portions are formed by extending the top portions of the inner walls of the respective insulating bobbins in a circumferential direction, and the connecting wires of the main winding wire or the auxiliary winding wire are disposed so as to be laid on outer circumferential sides of the extended portions.